Read, from cover to cover, the Case Manager Handbook.
Know, ADA rules and regulations - especially important are knowing the employers rights and the employees rights. A question I remember from 1999 was about the employee having to have the essential qualifications to be able to perform the job. Another was the number of employees and employer has to have in order to be exempt from ADA rules and regs.
Know of these things and what they stand for (hint - the internet, God bless it, was so helpful for this):
Railroad Workers Act
Black Lung Act (Coal-miners)
HIPAA (there should definitely be a question on this because if it's importance)
Know some of the basic tests that are used to assess a person's intelligence level and job ability (can't think of them off hand).
MEDICARE!!! Be aware of the history and basic rules and regs. There was a question on a 24 year old kidney transplant patient qualifying for medicare. Another one on who would be primary - the spouse under age 62 with private health insurance, or the patient who is on Medicare. Know what it does and does not cover, difference between Part A and Part B.
Medicaid - know who qualifies, what it does and does not cover.
Workers Compensation - how it came about, what it does and does not do. Remember some are state regulated, some are federally regulated. This is where Longshoreman's Act, Railroad workers, ect. comes in to play.
HIV/AIDS considerations in case management.
Rehabilitation - what a program should involve. Remember there are several different types of rehab, KNOW aspects of Vocational Rehabilitation. What test voc rehab counselors use to assess abilities. There were 2 questions on tests I'd never heard of! So, I guessed.
Oxygen! What p02 or O2 Sat must you have for Medicare to approve oxygen? The cost and usage difference between liquid and gas. Considerations you must make when deciding on systems for a patient.
Those are the one's I can think of off the top of my head. I hope some recent test takers post here for you!